Chapter 8. DMA Controller
8-1
Chapter 8
DMA Controller
This chapter describes the DMA controller of the MPC8240—the operation of the two
DMA channels, the function of the DMA transfer types, the DMA descriptors’ format, and
the programming details for the DMA registers and their features.
8.1 DMA Overview
The MPC8240’s DMA controller transfers blocks of data independent of the local
processor or PCI hosts. Data movement occurs on the PCI and/or memory bus. The
MPC8240 has two DMA channels, each with a 64-byte queue to facilitate the gathering and
sending of data. Both the local processor and PCI masters can initiate a DMA transfer.
Some of the features of the MPC8240 DMA unit are:
•
Two DMA channels (0 and 1)
•
Both channels accessible by processor core and remote PCI masters
•
Misaligned transfer capability
•
Chaining mode (including scatter gathering)
•
Direct mode
•
Interrupt on completed segment, chain, and error conditions
•
Four DMA transfer types:
— Local memory to local memory
— PCI memory to PCI memory
— PCI memory to local memory
— Local memory to PCI memory
The DMA controller functions as a PCI agent relative to the other internal resources of the
MPC8240.
Summary of Contents for MPC8240
Page 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Page 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Page 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Page 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Page 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Page 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Page 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Page 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Page 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Page 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Page 516: ...16 14 Watchpoint Trigger Applications ...
Page 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Page 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Page 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...